The band was originally called Amon, and recorded two demos under this name, which were later released on CD as "Amon: Feasting The Beast". They changed the name to Deicide in late 1989, just prior to the recording of the self-titled debut. This was done at the insistence of their then-label, Roadrunner Records, because there was a song called "'Amon' Belongs to 'Them'" on the King Diamond album, "Conspiracy".
Deicide:
\De"i*cide\, n. [L. deicida a deicide (in sense 2); deus god + c[ae]dere to cut, kill: cf. F. d['e]icide.] Read more on Last.fm